As a probe which is used for testing DUTs in the state of wafer, a probe is known which comprises a membrane, a first anisotropic conductive rubber, a first wiring board, a second anisotropic conductive rubber, and a second wiring board (refer to Patent Document 1, for example).
In this probe of five-layer structure, the first anisotropic conductive rubber is interposed between the membrane and the first wiring board, and the second anisotropic conductive rubber is interposed between the first wiring board and the second wiring board.
These anisotropic conductive rubbers ensure pressing forces for establishing electrical conductivity between the membrane and the first wiring board and electrical conductivity between the first wiring board and the second wiring board, and absorb positional errors of the semiconductor wafer, the membrane, the first wiring board, and the second wiring board.